Move weapon logic from Player to Arsenal. (#26)

- Add remaining round count in `Weapon`, defaulted to -1 (infinite).
- Add main (permanent) and special (temporary) weapons to `Arsenal`.
- Auto-switch back to main weapon after special has no more rounds and is idle.

Author: karnkaul

src/spaced/spaced/game/arsenal.cpp

@@ -0,0 +1,50 @@
+#include <spaced/game/arsenal.hpp>
+
+namespace spaced {
+using bave::Seconds;
+using bave::Shader;
+
+auto Arsenal::get_weapon() const -> Weapon const& {
+	if (m_special) { return *m_special; }
+	return m_primary;
+}
+
+auto Arsenal::get_weapon() -> Weapon& {
+	return const_cast<Weapon&>(std::as_const(*this).get_weapon()); // NOLINT(cppcoreguidelines-pro-type-const-cast)
+}
+
+void Arsenal::tick(IWeaponRound::State const& round_state, bool const fire, Seconds const dt) {
+	tick_weapons(dt);
+	check_switch_weapon();
+	if (fire) { fire_weapon(round_state.muzzle_position); }
+	tick_rounds(round_state, dt);
+}
+
+void Arsenal::draw(Shader& shader) const {
+	for (auto const& round : m_rounds) { round->draw(shader); }
+}
+
+void Arsenal::tick_weapons(Seconds const dt) {
+	m_primary.tick(dt);
+
+	if (m_special) {
+		m_special->tick(dt);
+		// if the special weapon has no more rounds and is idle, reset it.
+		if (m_special->get_rounds_remaining() == 0 && m_special->is_idle()) { m_special.reset(); }
+	}
+}
+
+void Arsenal::check_switch_weapon() {
+	// if there is a next weapon on standby and the current weapon is idle, switch to the next weapon.
+	if (m_next && get_weapon().is_idle()) { m_special = std::move(m_next); }
+}
+
+void Arsenal::fire_weapon(glm::vec2 const muzzle_position) {
+	if (auto round = get_weapon().fire(muzzle_position)) { m_rounds.push_back(std::move(round)); }
+}
+
+void Arsenal::tick_rounds(IWeaponRound::State const& round_state, Seconds const dt) {
+	for (auto const& round : m_rounds) { round->tick(round_state, dt); }
+	std::erase_if(m_rounds, [](auto const& round) { return round->is_destroyed(); });
+}
+} // namespace spaced

src/spaced/spaced/game/arsenal.hpp

@@ -0,0 +1,32 @@
+#pragma once
+#include <spaced/game/weapons/gun_kinetic.hpp>
+
+namespace spaced {
+// Arsenal models a main/primary weapon, and an possible special weapon.
+// Weapons only switch when they are idle.
+class Arsenal {
+  public:
+	explicit Arsenal(Services const& services) : m_primary(services) {}
+
+	[[nodiscard]] auto get_weapon() const -> Weapon const&;
+	[[nodiscard]] auto get_weapon() -> Weapon&;
+
+	[[nodiscard]] auto is_special_active() const -> bool { return m_special != nullptr; }
+
+	void set_special(std::unique_ptr<Weapon> weapon) { m_next = std::move(weapon); }
+
+	void tick(IWeaponRound::State const& round_state, bool fire, bave::Seconds dt);
+	void draw(bave::Shader& shader) const;
+
+  private:
+	void tick_weapons(bave::Seconds dt);
+	void check_switch_weapon();
+	void fire_weapon(glm::vec2 muzzle_position);
+	void tick_rounds(IWeaponRound::State const& round_state, bave::Seconds dt);
+
+	GunKinetic m_primary;				 // main weapon
+	std::unique_ptr<Weapon> m_special{}; // special weapon
+	std::unique_ptr<Weapon> m_next{};	 // next special weapon (on standby until current weapon is idle)
+	std::vector<std::unique_ptr<Weapon::Round>> m_rounds{};
+};
+} // namespace spaced

src/spaced/spaced/game/player.cpp

@@ -7,7 +7,6 @@
 
 // temp for testing
 #include <spaced/game/weapons/gun_beam.hpp>
-#include <spaced/game/weapons/gun_kinetic.hpp>
 
 namespace spaced {
 using bave::im_text;
@@ -19,11 +18,7 @@ using bave::RoundedQuad;
 using bave::Seconds;
 using bave::Shader;
 
-Player::Player(Services const& services, std::unique_ptr<IController> controller) : m_services(&services), m_controller(std::move(controller)) {
-	setup_ship();
-
-	debug_switch_weapon();
-}
+Player::Player(Services const& services, std::unique_ptr<IController> controller) : m_services(&services), m_controller(std::move(controller)) { setup_ship(); }
 
 void Player::on_focus(bave::FocusChange const& /*focus_changed*/) { m_controller->untap(); }
 
@@ -35,32 +30,17 @@ void Player::tick(std::span<NotNull<IDamageable*> const> targets, Seconds const
 	auto const y_position = m_controller->tick(dt);
 	set_y(y_position);
 
-	auto const muzzle_position = get_muzzle_position();
-	if (m_controller->is_firing() && m_debug.shots_remaining > 0) {
-		if (auto round = m_weapon->fire(muzzle_position)) {
-			m_weapon_rounds.push_back(std::move(round));
-			--m_debug.shots_remaining;
-		}
-	}
-
-	auto const round_state = IWeaponRound::State{.targets = targets, .muzzle_position = muzzle_position};
-	for (auto const& round : m_weapon_rounds) { round->tick(round_state, dt); }
-	std::erase_if(m_weapon_rounds, [](auto const& charge) { return charge->is_destroyed(); });
-
-	m_weapon->tick(dt);
+	auto const round_state = IWeaponRound::State{.targets = targets, .muzzle_position = get_muzzle_position()};
+	m_arsenal.tick(round_state, m_controller->is_firing(), dt);
 
 	m_exhaust.set_position(get_exhaust_position());
-
 	m_exhaust.tick(dt);
-
-	if (m_debug.shots_remaining <= 0) { debug_switch_weapon(); }
 }
 
 void Player::draw(Shader& shader) const {
 	m_exhaust.draw(shader);
 	ship.draw(shader);
-
-	for (auto const& round : m_weapon_rounds) { round->draw(shader); }
+	m_arsenal.draw(shader);
 }
 
 void Player::setup(WorldSpec::Player const& spec) {
@@ -83,15 +63,28 @@ void Player::set_controller(std::unique_ptr<IController> controller) {
 	m_controller = std::move(controller);
 }
 
+void Player::setup_ship() {
+	auto const& layout = m_services->get<ILayout>();
+	ship.transform.position.x = layout.get_player_x();
+	auto rounded_quad = RoundedQuad{};
+	rounded_quad.size = layout.get_player_size();
+	rounded_quad.corner_radius = 20.0f;
+	ship.set_shape(rounded_quad);
+}
+
 void Player::do_inspect() {
 	if constexpr (bave::imgui_v) {
 		if (ImGui::TreeNodeEx("Controller", ImGuiTreeNodeFlags_Framed | ImGuiTreeNodeFlags_DefaultOpen)) {
 			m_controller->inspect();
 			ImGui::TreePop();
 		}
 		if (ImGui::TreeNodeEx("Weapon", ImGuiTreeNodeFlags_Framed | ImGuiTreeNodeFlags_DefaultOpen)) {
-			m_weapon->inspect();
-			im_text("shots remaining: {}", m_debug.shots_remaining);
+			if (ImGui::Button("Switch to Beam")) {
+				auto beam = std::make_unique<GunBeam>(*m_services);
+				beam->rounds = 2;
+				m_arsenal.set_special(std::move(beam));
+			}
+			m_arsenal.get_weapon().inspect();
 			ImGui::TreePop();
 		}
 		if (ImGui::TreeNodeEx("Status", ImGuiTreeNodeFlags_Framed | ImGuiTreeNodeFlags_DefaultOpen)) {
@@ -100,26 +93,4 @@ void Player::do_inspect() {
 		}
 	}
 }
-
-void Player::setup_ship() {
-	auto const& layout = m_services->get<ILayout>();
-	ship.transform.position.x = layout.get_player_x();
-	auto rounded_quad = RoundedQuad{};
-	rounded_quad.size = layout.get_player_size();
-	rounded_quad.corner_radius = 20.0f;
-	ship.set_shape(rounded_quad);
-}
-
-void Player::debug_switch_weapon() {
-	if (m_weapon && !m_weapon->is_idle()) { return; }
-
-	if (dynamic_cast<GunKinetic const*>(m_weapon.get()) != nullptr) {
-		m_weapon = std::make_unique<GunBeam>(*m_services);
-		m_debug.shots_remaining = 2;
-		return;
-	}
-
-	m_weapon = std::make_unique<GunKinetic>(*m_services);
-	m_debug.shots_remaining = 10;
-}
 } // namespace spaced

src/spaced/spaced/game/player.hpp

@@ -2,9 +2,9 @@
 #include <bave/graphics/particle_system.hpp>
 #include <bave/graphics/shape.hpp>
 #include <bave/logger.hpp>
+#include <spaced/game/arsenal.hpp>
 #include <spaced/game/controller.hpp>
 #include <spaced/game/health.hpp>
-#include <spaced/game/weapon.hpp>
 #include <spaced/game/world_spec.hpp>
 
 namespace spaced {
@@ -30,6 +30,8 @@ class Player : public bave::IDrawable {
 	void set_controller(std::unique_ptr<IController> controller);
 	[[nodiscard]] auto get_controller() const -> IController const& { return *m_controller; }
 
+	void set_special_weapon(std::unique_ptr<Weapon> weapon) { m_arsenal.set_special(std::move(weapon)); }
+
 	void inspect() {
 		if constexpr (bave::debug_v) { do_inspect(); }
 	}
@@ -41,17 +43,12 @@ class Player : public bave::IDrawable {
 	void setup_ship();
 
 	void do_inspect();
-	void debug_switch_weapon();
 
 	bave::Logger m_log{"Player"};
 	bave::NotNull<Services const*> m_services;
 	std::unique_ptr<IController> m_controller;
 	bave::ParticleEmitter m_exhaust{};
-	std::unique_ptr<Weapon> m_weapon{};
-	std::vector<std::unique_ptr<Weapon::Round>> m_weapon_rounds{};
 
-	struct {
-		int shots_remaining{};
-	} m_debug{};
+	Arsenal m_arsenal{*m_services};
 };
 } // namespace spaced

src/spaced/spaced/game/weapon.cpp

@@ -0,0 +1,10 @@
+#include <bave/imgui/im_text.hpp>
+#include <spaced/game/weapon.hpp>
+
+namespace spaced {
+using bave::im_text;
+
+void Weapon::do_inspect() {
+	if constexpr (bave::imgui_v) { im_text("rounds remaining: {}", get_rounds_remaining()); }
+}
+} // namespace spaced

src/spaced/spaced/game/weapon.hpp

@@ -12,6 +12,8 @@ class Weapon : public bave::Polymorphic {
 
 	explicit Weapon(Services const& services, std::string name) : m_log{std::move(name)}, m_layout(&services.get<ILayout>()) {}
 
+	[[nodiscard]] auto get_rounds_remaining() const -> int { return rounds < 0 ? 1 : rounds; }
+
 	virtual auto fire(glm::vec2 muzzle_position) -> std::unique_ptr<Round> = 0;
 	[[nodiscard]] virtual auto is_idle() const -> bool = 0;
 
@@ -21,9 +23,12 @@ class Weapon : public bave::Polymorphic {
 		if constexpr (bave::debug_v) { do_inspect(); }
 	}
 
+	int rounds{-1};
+
   protected:
 	[[nodiscard]] auto get_layout() const -> ILayout const& { return *m_layout; }
-	virtual void do_inspect() {}
+
+	virtual void do_inspect();
 
 	bave::Logger m_log{};
 

src/spaced/spaced/game/weapons/gun_beam.cpp

@@ -103,8 +103,9 @@ GunBeam::GunBeam(Services const& services) : Weapon(services, "GunBeam") {
 }
 
 auto GunBeam::fire(glm::vec2 const muzzle_position) -> std::unique_ptr<Round> {
-	if (!is_idle() || m_reload_remain > 0s) { return {}; }
+	if (!is_idle() || m_reload_remain > 0s || rounds == 0) { return {}; }
 
+	if (rounds > 0) { --rounds; }
 	m_fire_remain = config.fire_duration;
 	m_reload_remain = 0s;
 	return std::make_unique<LaserCharge>(&get_layout(), config, muzzle_position);
@@ -124,6 +125,7 @@ void GunBeam::tick(Seconds const dt) {
 void GunBeam::do_inspect() {
 	if constexpr (bave::imgui_v) {
 		im_text("type: GunBeam");
+		Weapon::do_inspect();
 		ImGui::DragFloat("beam height", &config.beam_height, 0.25f, 1.0f, 100.0f);
 		auto fire_duration = config.fire_duration.count();
 		if (ImGui::DragFloat("fire duration (s)", &fire_duration, 0.25f, 0.25f, 10.0f)) { config.fire_duration = Seconds{fire_duration}; }

src/spaced/spaced/game/weapons/gun_kinetic.cpp

@@ -10,8 +10,9 @@ using bave::Seconds;
 GunKinetic::GunKinetic(Services const& services) : Weapon(services, "GunKinetic") { projectile_config.tint = services.get<Styles>().rgbas["black"]; }
 
 auto GunKinetic::fire(glm::vec2 const muzzle_position) -> std::unique_ptr<Round> {
-	if (m_reload_remain > 0s) { return {}; }
+	if (m_reload_remain > 0s || rounds == 0) { return {}; }
 
+	if (rounds > 0) { --rounds; }
 	m_reload_remain = reload_delay;
 	return std::make_unique<Projectile>(&get_layout(), projectile_config, muzzle_position);
 }
@@ -23,6 +24,7 @@ void GunKinetic::tick(Seconds const dt) {
 void GunKinetic::do_inspect() {
 	if constexpr (bave::imgui_v) {
 		im_text("type: GunKinetic");
+		Weapon::do_inspect();
 		ImGui::DragFloat2("projectile size", &projectile_config.size.x);
 		ImGui::DragFloat("x speed", &projectile_config.x_speed, 10.0f, 100.0f, 10000.0f);
 		auto tint = projectile_config.tint.to_vec4();